Introduction
============

scanloc for |scname| :cite:p:`seiscomp` is optimzed for monitoring local and
micro seismicity within small as
well as large seismic monitoring networks in low and high seismicity environments.
Typical networks consist of 5 to 20 stations
and sometimes even many more were the station distances are in the range of
hundreds of meters to tens of kilometers.

scanloc makes use of the cluster search algorithm DBSCAN :cite:p:`dbscan` to
associate detected seismic phases to one or many potential seismic events.
While the cluster search itself is based on P phases only, in a second step S
picks and more P phases are associated to better locate the event.

In order to provide high-quality picks from S phases, a new
:ref:`S-phase picker <scanloc-spicker>` is distributed
along with scanloc. The S picker allows to identify S phases on the horizontal
components or on the vertical components if the horizontals should be unavailable.
A :ref:`user-friendly debugger GUI <scanloc-spick-debugger>` allows the interactive
tuning of the S picker configuration parameters based on waveforms.

:ref:`Additonal auxiliary tools <sec-scanloc-aux-tools>` ship with the scanloc
package to support detailed tuning and realistic playbacks.


Applications
------------

scanloc is a backbone module in |scname| systems for many applications including

* Real-time monitoring of local and regional earthquakes,
* Re-processing of historical data for more complete seismicity catalogs,
* Monitoring of natural and induced seismicity in industrial environments e.g. at

  * geothermal plants,
  * oil and gas production,
  * underground gas storages,
  * open and deep mines,

* Integration of :ref:`teleseismic events<scanloc-zero-weight>` detected by
  local monitoring networks
* :ref:`Association of P and S phases <scanloc-assoc>` to detections by other
  instances e.g. :cite:t:`ccloc` or :cite:t:`lambda`.


Examples from science
---------------------

scanloc has been routinely applied, demonstrated, promoted and discussed with
scientists and the SeisComP community in scientific publications and at
international science conferences.

Examples:

#. A.F. Bell, P.C. La Femina, M. Ruiz, F. Amelung, M. Bagnardi, C. J. Bean, B.
   Bernard, C. Ebinger, M. Gleeson, J. R. Grannell, S. Hernandez, M. Higgins, C.
   Liorzou, P. Lundgren, N. J. Meier, M. Möllhoff, S.-J. Oliva, A. G. Ruiz and
   M. J. Stock: Caldera resurgence during the 2018 eruption of Sierra Negra
   volcano, Galápagos Islands, 2021, Nat. Commun., 12, 1397,
   `doi: 10.1038/s41467-021-21596-4 <https://doi.org/10.1038/s41467-021-21596-4>`_.
#. F. Grigoli, L. Scarabello, M. Boese, B. Weber, S. Wiemer, J. F. Clinton:
   Pick- and waveform-based techniques for real-time detection of induced seismicity,
   2018, Geophys. J. Int., 213:2, `doi: 0.1093/gji/ggy019 <https://doi.org/10.1093/gji/ggy019>`_.
#. J. Clinton, F. Grigoli, T. Diehl, T. Kraft, L. Scarabello, M. Hermann, P. Kaestli,
   M. Boese, S. Wiemer: Advanced  Real-time Monitoring for Natural and Induced
   seismic sequences, 2018, Geophyscial Research Abracts, EGU General Assembly,
   Vol. 20,
   `abstract: EGU2018-9480-2 <https://meetingorganizer.copernicus.org/EGU2018/EGU2018-9480.pdf>`_.
#. F. Grigoli, M. Boese, L. Scarabello, T. Diehl, B. Weber, S. Wiemer, J. F. Clinton:
   Picking vs Waveform based detection and location methods for induced seismicity
   monitoring, 2018, JpGU2018, Japan,
   `abstract: SSS03-05 <https://confit.atlas.jp/guide/event/jpgu2018/subject/SSS03-05/detail>`_.
#. F. Grigoli, M. Boese, L. Scarabello, T. Diehl, B. Weber, S. Wiemer, J. F. Clinton:
   Picking vs Waveform based detection and location methods for induced seismicity
   monitoring, 2017, Geophyscial Research Abracts, EGU General Assembly, Vol. 19,
   `abstract: EGU2017-10562 <https://meetingorganizer.copernicus.org/EGU2017/EGU2017-10562.pdf>`_.
#. D. Roessler, J. Becker, E. Ellguth, R. Henneberger, S. Herrnkind, B. Weber:
   Cluster-search based monitoring of local earthquakes in SeisComP3, 2016,
   AG Seismology - 42. meeting, Bad Salzschlirf, Germany
#. D. Roessler, E. Ellguth, S. Herrnkind, B. Weber, R. Henneberger, H. Blanck:
   Cluster-search based monitoring of local earthquakes in SeisComP3, 2016,
   AGU Fall Meeting, San Francisco, USA,
   `abstract S31E-06 <https://agu.confex.com/agu/fm16/meetingapp.cgi/Paper/119780>`_.